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Full text of "The manufacture and properties of iron and steel"

THE UNITED STATES.                                       479
Fe ........................	......................   51.00
SiOa ....................	......................     9.00
AlaPs .....................	......................     3.75
Cab.;. ................. .	.  ...............     0.75
p ..........................	..... . ................     0.40
s ..........................	......................     0.10
SOFT ORE   (HEMATITE).
The so-called soft ore of Birmingham is the result of ages of atmospheric influence upon a deposit of hard calcareous hematite. The disintegrating action has not only softened the mass, hut the percolating water has removed the lime, and, as a consequence, the percentage of iron is higher in this soft ore than in the underlying hard and limey deposit on the dip. The extent of this decomposed layer varies on the dip, in some places being 300 feet, while in other places the hard ore appears on the surface. When the overburden is stripped off, there is found a seam of ore, quite soft, of a deep red or purple color, the so-called "gouge." It may be only a few inches thick and may run up to two or even three feet. Under this comes the solid ore, diminishing in iron as the depth increases. The best quality of "gouge" will carry 52 per cent, of iron, while ten feet down the limit of good ore is reached. Including this "gouge" it is found that the first ten feet of the seam will average about 47 per cent, in iron, while the second ten feet will run about 42 per cent. In former times the rule was to send to the furnace "anything that was red," but operations are now limited to the upper ten feet. An average of stockhouse samples shows as follows:
SOFT   BED  QBE.
Wet.                Dry.
Fe  ........................    47.24               50.80
S102.......................     17.20               18.50
Al2Oa......................       3.35                 3.60
CaO .......................      1.12                 1.20
Water  .....................      7.00
HARD RED ORE.
The relation of the deposits of soft and hard ores is shown by Fig. XXII-J, which is copied from Dr. Phillips. Sometimes the hard ore reaches to the surface, and sometimes both soft and hard ores of the good variety are lacking, but usually the hard good ore is found, reaching to a great depth. Not many years ago the soft